<lisa>A client must deal with versions the way it deals with any resource:
- if it has never before retrieved the body, it has NO WAY of knowing
whether the body has changed, and has NO REFERENCE POINT against which to
compare that anyway! It's meaningless to say that the content "shouldn't
have changed" since a client which has never before seen the content can't
tell the difference.
- When it does retrieve the body, it should retrieve the ETag.
- When it wants to see if the body has changed, it should compare the
ETag.</lisa>
I disagree. What you are saying is true of regular resources, but it should
not be true of immutable versions. That's part of the funtamental semantics
that versioning adds to WebDAV. I don't think it is at all unreasonable for
someone (or some application or baseline) to assume that immutable versions
it references will never change other than deletion. In some cases, this is
even a legal requirement.